genetics ch.21
A DNA microarray is a silica or plastic slide that contains ______ in an area the size of a(n) ______. tens of thousands of different DNA sequences; printer paper tens of thousands of copies of the same DNA sequence; postage stamp tens of thousands of copies of the same DNA sequence; printer paper tens of thousands of different DNA sequences; postage stamp
tens of thousands of different DNA sequences; postage stamp
What is a molecular marker? A labeled probe that can hybridize to a unique sequence on chromosomal DNA A segment of DNA that can be uniquely identified using molecular tools A dye that specifically stains DNA A fluorescent molecule that can be covalently attached to a single-stranded DNA probe
A segment of DNA that can be uniquely identified using molecular tools
Which of the following techniques is commonly used for cytogenetic mapping? In situ hybridization Pedigree analysis Chromosome walking Shotgun sequencing
In situ hybridization
What is a metagenome? Multiple choice question. A collection of genes from an environmental sample An exceptionally large genome A contig composed of numerous smaller clones The entire genome sequence of an organism
A collection of genes from an environmental sample
Another term for DNA microarray is ______ ______
gene chip
A collection of organisms of the same species in which each strain carries one gene whose function has been inactivated is called a(n) ____ collection.
knockout
Many microorganisms that live in soil, water, and the human intestinal tract are difficult to study because they may require the presence of a complex microbial community. they have very high mutation rates, which makes it difficult to keep them alive. their genomes are too large to sequence using traditional methods. researchers may not understand their growth requirements.
they may require the presence of a complex microbial community. researchers may not understand their growth requirements.
The set of all RNA molecules that are transcribed in one cell or a population of cells is called the ____
transcriptome
What is a sequence-tagged site? Multiple choice question. A specific DNA sequence that can be amplified by PCR A site on a chromosome that hybridizes with a fluorescently-labeled DNA probe (Hybridizing with a complementary DNA sequence is not unique to sequence-tag sites.) A single-stranded DNA probe that contains biotin-labeled nucleotides A DNA sequence that can be cut by a restriction enzyme
A specific DNA sequence that can be amplified by PCR
In a FISH experiment, what molecule is incorporated into the single-stranded DNA probes that later allows for detection of the probes? Avidin Biotin DAPI Fluorescent molecule (The fluorescent label is associated with avidin, rather than with the biotin incorporated into the probes.)
Biotin
Which of the following processes is used for physical mapping? Hybridizing biotin-containing single-stranded DNA probes to chromosomal DNA Cloning fragments of chromosomal DNA Calculating the frequency of recombination between two genetic loci
Cloning fragments of chromosomal DNA
What was the source of DNA for the Human Genome Project? DNA from several anonymous volunteers DNA from a single anonymous individual DNA from Craig Venter DNA from James Watson
DNA from several anonymous volunteers
Genes encoding proteins that participate in a common metabolic pathway are often expressed simultaneously. What experimental technique would be most appropriate for identifying genes whose mRNAs are expressed together? Mass spectrometry Tandem mass spectrometry DNA microarray BLAST Two-dimensional gel electrophoresis
DNA microarray
True or false: The Human Genome Project used DNA from a single individual to obtain the human genome sequence. True false question. True (The human DNA that was used for the Human Genome Project came from several volunteers who remained anonymous.) False
False
The location of a fluorescently-labeled probe relative to the banding pattern of a chromosome is determined by comparing the results of a FISH experiment to a sample of chromosomes that have been stained with ____
Giemsa
What stain is used to produce banding patterns on chromosomes so that the location of a bound probe in a FISH experiment can be compared to banded chromosomes? Phenol red DAPI Coomassie blue Giemsa
Giemsa
How is genome sequencing likely to improve our understanding of human disease? It may lead to the identification of human genes involved in disease. It will enable us to prevent new mutations from occurring in the human genome. It can provide information about genes found in pathogens that infect humans.
It may lead to the identification of human genes involved in disease. It can provide information about genes found in pathogens that infect humans.
Which of the following are potential applications of DNA microarrays? Microbial strain identification Tumor profiling Studying genetic variation Identification of protein-protein interactions Comparison of cell-specific gene expression Comparison of protein expression levels
Microbial strain identification Tumor profiling Studying genetic variation Comparison of cell-specific gene expression
Arrange the steps involved in a metagenomic study in the correct order. Sequence DNA Lyse cells from the sample Obtain an environmental sample Extract and purify DNA Filter the sample to collect cells Insert DNA into cloning vectors, and transform them into host cells
Obtain an environmental sample Filter the sample to collect cells Lyse cells from the sample Extract and purify DNA Insert DNA into cloning vectors, and transform them into host cells Sequence DNA
If DNA is collected from a haploid cell, how many bands will be produced by an STS that is amplified by PCR and subjected to gel electrophoresis? Two (A haploid cell will have only one copy of the sequence being amplified by PCR.) Four Either one or two One
One
In pyrosequencing, the incorporation of a nucleotide into a growing DNA strand is monitored by measuring the release of deoxyribose. cAMP. a fluorescently labeled probe.
PPi.
If you wished to compare the transcriptome of healthy cells versus diseased cells, which method would you choose? Multiple choice question. Microarray analysis Mass spectrometry Chromatin immunoprecipitation Two-dimensional gel electrophoresis RNA-sequencing (RNA-Seq)
RNA-sequencing (RNA-Seq)
What is high-throughput sequencing? The sequencing of both strands of a DNA fragment at the same time The simultaneous sequencing and expression of multiple DNA samples The ability to rapidly sequence large amounts of DNA
The ability to rapidly sequence large amounts of DNA
What is the goal of a genome-sequencing project? To identify polymorphic sequences in the genome of a given species To determine the DNA sequence of the entire genome of a given species To identify all disease-causing mutations in the genome of a given species To compare the genomes of two closely related species
To determine the DNA sequence of the entire genome of a given species
Arrange the steps involved in fluorescence in situ hybridization (FISH) in the correct order. Hybridize chromosomal DNA to single-stranded DNA probes containing biotin View with a fluorescence microscope Treat cells with agents that cause them to swell and fix them onto a slide Add fluorescently labeled avidin Denature chromosomal DNA
Treat cells with agents that cause them to swell and fix them onto a slide Denature chromosomal DNA Hybridize chromosomal DNA to single-stranded DNA probes containing biotin Add fluorescently labeled avidin View with a fluorescence microscope
Chromatin immunoprecipitation (ChIP) is a technique that is used to measure gene expression levels. analyze DNA-protein interactions. sequence the DNA or RNA of a cell. separate a mixture of cellular proteins.
analyze DNA-protein interactions.
"FISH" stands for ______ in situ hybridization.
fluorescence
A knockout collection is a collection of organisms of the same species in which each strain has all of the genes for a specific metabolic pathway knocked out. carries only a few genes. can be induced to express specific sets of genes. has one gene knocked out.
has one gene knocked out.
The ability to rapidly sequence large amounts of DNA is called ___- ____sequencing.
high throughput
A method called chromatin ______ (ChIP) can be used to determine whether proteins can bind to a particular region of DNA.
immunoprecipitation
To analyze a microsatellite sequence, a scientist must first amplify it by PCR. This requires the use of PCR _____ that flank the repeated sequence in the microsatellite.
primers
In linkage mapping, the distance between sites on the same chromosome is determined by calculating the frequency of polymorphic alleles. recombinant offspring. mutant phenotypes. new mutations.
recombinant offspring.
A site that can be uniquely amplified by PCR is called a _____ - _____site, or STS.
sequence tagged
One of the methods that is used for genome-sequencing projects involves the sequencing of randomly generated DNA fragments followed by identification of overlapping regions in the DNA sequence. This method is called ___sequencing.
shotgun
What outcomes have already resulted from the Human Genome Project? Cures for most genetic diseases Cloning of extinct species Improved DNA sequencing technology Sequence data for the 22 human autosomes Improvements in cloning technology Affordable personalized medicine Sequence data for the human X and Y chromosomes Improvements in software for accessing and analyzing sequence data
Improved DNA sequencing technology Sequence data for the 22 human autosomes Improvements in cloning technology Sequence data for the human X and Y chromosomes Improvements in software for accessing and analyzing sequence data
Genome-wide analysis of gene expression is possible via real time PCR. mass spectrometry. DNA microarrays. Northern blots.
DNA microarrays.
What does the term mapping mean in the context of genetics? Determining the locations of genes along individual chromosomes Identifying the sequence of evolutionary events that have occurred in the past Determining the locations of specific proteins in subcellular organelles
Determining the locations of genes along individual chromosomes
The transcriptome is the set of all ______ produced in one cell or a population of cells. ribosomes DNA molecules chromosomes RNA molecules proteins
RNA molecules
During FISH, the location of a bound probe can be detected through the emission of ____- light.
fluorescent
The most common method of in situ hybridization uses ______ DNA probes. fluorescent radioactive fragmented 4 kb
fluorescent
A microsatellite can be amplified by PCR using primers that are located within the microsatellite. on both sides of the microsatellite. anywhere on the chromosome that contains the microsatellite.
on both sides of the microsatellite.
The type of mapping in which a gene is localized to a site within a chromosomal banding pattern is _____ mapping.
cytogenetic
A diagram that shows the relative locations of genes or other DNA segments along a chromosome is called a genetic _____
map
Which of the following is an accurate description of shotgun sequencing? Random DNA fragments are sequenced, and overlapping parts of the sequence are identified. Chromosomal DNA is mapped, and a set of overlapping clones from a contig is selected for DNA sequencing. A probe from a known DNA location is used to identify an overlapping clone. Successive iterations of this procedure lead to cloning of a gene.
Random DNA fragments are sequenced, and overlapping parts of the sequence are identified.
What is represented in a genetic map? All of the genes that contribute to a complex phenotype The inheritance of a disease or other trait in a family over several generations The locations of genes or other DNA segments along a chromosome A comparison of the DNA sequences of the same gene in several closely related species
The locations of genes or other DNA segments along a chromosome
What is represented in a genetic map? The inheritance of a disease or other trait in a family over several generations All of the genes that contribute to a complex phenotype A comparison of the DNA sequences of the same gene in several closely related species The locations of genes or other DNA segments along a chromosome
The locations of genes or other DNA segments along a chromosome
Why are microbes that live in water, soil, and the human intestinal tract difficult to study in the laboratory? Their DNA has a different structure than that of most organisms. They are difficult to culture. They are highly susceptible to viral infection when placed outside of their normal environments. (It is difficult for scientists to determine the growth requirements for these cells.) They have high mutation rates.
They are difficult to culture.
What is the goal of cytogenetic mapping? To determine whether there is a mutation in a gene that causes a particular disease To determine the DNA sequence of a gene To localize a gene to a site within a chromosomal banding pattern To determine the order of DNA fragments within a long DNA clone
To localize a gene to a site within a chromosomal banding pattern
True or false: Molecular genetic technology such as gene cloning, contig construction, and DNA sequencing have been improved as a direct result of the efforts of the Human Genome Project. True false question. True False (One of the goals of the Human Genome Project was to develop technological advances in genetic methodology. All of the techniques listed here have been improved as a direct result of the Human Genome Project.)
True
The total genetic composition of an organism or species is the ______
genome
A research endeavor with the goal of determining the sequence of DNA bases in an organism's entire genome is called a(n) ___-___ project.
genome sequencing
During in situ hybridization, a DNA probe made from a cloned gene binds to any chromosome that contains a gene of the same size. both arms of the chromosome where the gene is located. its complementary sequence on a particular chromosome.
its complementary sequence on a particular chromosome.
A gene chip is also called a(n) Multiple choice question. chromatin immunoassay. DNA microarray. Northern blot. Southern blot.
DNA microarray.
The study of a complex mixture of genetic material obtained from an environmental sample is called
metagenomics
What is a microsatellite? A site in the genome where the distance between two restriction sites varies among individuals A small circular DNA molecule that is replicated independently of the chromosomes Any molecular marker that is found at a unique site in the genome and can be amplified by PCR A short DNA sequence repeated many times in a row
A short DNA sequence repeated many times in a row
During a researcher's in situ hybridization procedure, what causes the probe to stick to the chromosome? A ligand attached to the probe binds its receptor on the chromosome (The probe itself binds to sequences on the chromosome.) Promiscuous base pairing to any other DNA Complementary base pairing to the corresponding gene Interactions between the probe and histone proteins (Probes are typically small stretches of nucleic acid sequences that bind to other sequences, not to proteins.)
Complementary base pairing to the corresponding gene
Which mapping strategy involves cloning many pieces of DNA and characterizing their sizes and relative locations along a chromosome Cytogenetic mapping Linkage mapping Physical mapping
Physical mapping
Which mapping strategy involves cloning many pieces of DNA and characterizing their sizes and relative locations along a chromosome? Multiple choice question. Cytogenetic mapping Physical mapping Linkage mapping
Physical mapping
What is metagenomics? The study of genomes from large organisms The study of a complex mixture of genetic material from an environmental sample The study of very large genomes The study of genetic variation among different populations
The study of a complex mixture of genetic material from an environmental sample
The presence of two bands corresponding to a sequence-tagged site that has been amplified by PCR and subjected to gel electrophoresis indicates that the cell was homozygous for the STS. (If an individual has two copies that differ in the number of repeats in the microsatellite sequence (i.e heterozygous), the two PCR products obtained will be different in length.) STS did not contain a recognition site for a restriction enzyme. (If an individual has two copies that differ in the number of repeats in the microsatellite sequence (i.e heterozygous), the two PCR products obtained will be different in length.) cell was heterozygous for the STS. STS contained a recognition site for a restriction enzyme. (If an individual has two copies that differ in the number of repeats in the microsatellite sequence (i.e heterozygous), the two PCR products obtained will be different in length.)
cell was heterozygous for the STS.
In situ hybridization is a technique that is often used for cytogenetic mapping. linkage mapping. physical mapping.
cytogenetic mapping.
One of the goals of the Human Genome Project was to obtain a genetic linkage map of the human genome. This was accomplished by identifying millions of genetic markers and their locations on chromosomes. sequencing DNA from individuals known to have genetic diseases. hybridizing DNA probes corresponding to known genes to chromosomes and comparing the hybridization location to banding patterns.
identifying millions of genetic markers and their locations on chromosomes.
The mapping technique that relies on the frequency of recombinant offspring for determination of the distance between genetic loci is ______ mapping.
linkage
One of the benefits of sequencing the human genome is that it will make it easier to identify genes that cause disease when they are ______
mutated
Geneticists use several types of mapping strategies to identify the locations of genes. The approach that relies on DNA cloning techniques and allows computation of distances in base pairs is _____ mapping. The technique that is based on recombination frequencies between genes is _____mapping. The technique that locates genes relative to bands on chromosomes that are visible by microscopy is ____mapping.
physical, linkage and cytogenetic
An organism's genome is its complete set of proteins in all of its cells. total genetic composition. combination of alleles for a particular gene. mechanism of reproduction.
total genetic composition.
Match each type of chromosome mapping with the correct description. Cytogenetic mapping Linkage mapping Physical mapping Determination of the locations of specific sequences relative to bands on chromosomes Determining the relative locations of genes on a chromosome based on their frequency of genetic recombination Determining the locations of genes and other DNA sequences using DNA cloning techniques
Cytogenetic mapping-> Determination of the locations of specific sequences relative to bands on chromosomes Linkage mapping-> Determining the relative locations of genes on a chromosome based on their frequency of genetic recombination Physical mapping-> Determining the locations of genes and other DNA sequences using DNA cloning techniques
Each spot in a DNA microarray contains double-stranded DNA from a specific gene. (Single-stranded DNA is applied to each spot.) single-stranded DNA from many genes. (DNA from only one gene is included in each spot.) single-stranded DNA from a specific gene. double-stranded DNA from many genes.
single-stranded DNA from a specific gene..
Which of the following is an accurate description of shotgun sequencing? A probe from a known DNA location is used to identify an overlapping clone. Successive iterations of this procedure lead to cloning of a gene. Chromosomal DNA is mapped, and a set of overlapping clones from a contig is selected for DNA sequencing. Random DNA fragments are sequenced, and overlapping parts of the sequence are identified.
Random DNA fragments are sequenced, and overlapping parts of the sequence are identified.
RNA-sequencing (RNA-Seq) is used to compare transcriptomes in forensic investigations. in response to different environmental agents. in healthy versus diseased cells. in different stages of development. in forensic investigations. in different cell types.
in response to different environmental agents. in healthy versus diseased cells. in different stages of development. in different cell types.
In a metagenome sequencing project, DNA fragments from an environmental sample are cloned and transformed into host cells to produce a metagenomic _____, which is subjected to shotgun sequencing.
library
Identifying and localizing millions of genetic markers was an important procedure for the Human Genome Project's goal of obtaining a genetic ____ map of the human genome.
linkage
A fluorescence microscope is used to detect bound DNA probes in FISH. To detect the fluorescent molecules, the sample is illuminated with light, and then the fluorescent molecules emit ______ wavelength light, which is transmitted and detected. longer shorter
longer
During pyrosequencing, the release of pyrophosphate after addition of a nucleotide is monitored through a series of chemical reactions. In the first reaction, pyrophosphate and adenosine 5' phosphosulfate are the substrates for ATP synthesis by the enzyme ATP sulfurylase. The ATP produced in this reaction is combined with luciferin by the enzyme to ___ produce______
luciferase light
In genetics, the experimental process of determining the relative locations of genes or other DNA segments along individual chromosomes is referred to as ____
mapping
A collection of genes from an environmental sample is called a DNA library. (An environmental sample would have genomes from many species while a library contains sequences from only one species.) contig. cosmid. metagenome.
metagenome.
The technology that enables the expression of thousands of genes to be studied simultaneously is called a DNA____ .
microarray
A short repetitive DNA sequence, such as a dinucleotide sequence repeated many times in a row, is called a(n) amplified restriction fragment length polymorphism. single-nucleotide polymorphism. sequence-tagged site. restriction fragment length polymorphism. microsatellite.
microsatellite.
A segment of DNA that is located at a specific site along a chromosome and that has properties that allow it to be uniquely identified using molecular tools is called a(n) _____marker.
molecular
